The 5/16" RAIL shelf bracket is made of high performance anodized aluminum, with a smooth quarter rounded profile. This is the most selected support to pair with glass shelves for creating wall shelving and entertainment systems. When paired with our GLASSLINE shelves, the combo creates the illusion of a floating shelf. The heavy-duty 5/16" RAIL will support up to 77 pounds when used with a shelf of appropriate size. This metal bracket comes in two lengths - 24" and 32". There is also a 3/4" RAIL bracket which is designed to work with our composite and wooden shelves.